双级时效工艺对7050铝合金组织与性能的影响

·DOI10．3969/j．issn．1005-2895．2011．04．0062010-11-042010-12-015077109319837。[e-mail]70501221．3180202．310014、、XRD、SEM7050。705021、。F-R705022。51147050“”TG156．9A1005-2895201104-0021-05EffectofTwo-stageofAgingProcessingonMicrostructureandPropertiesof7050AluminumAlloyRENJian-ping12SONGRen-guo21．DepartmentofMechanicalandElectricalEngineeringTaizhouVocationalCollegeofScienceandTechnologyZhejiangTaizhou318020China2．TheMOEKeyLaboratoryofSpecialPurposeEquipmentandAdvancedProcessingTechnologyZhejiangUniversityofTechnologyHangzhou310014ChinaAbstractThetwo-stagelong-termagingof7050aluminumalloyintheprocessofage-hardeningpropertiesandmicrostructurewerestudiedbyhardnesstesttensiletestX-raydiffractionphaseandscanningelectronmicroscopySEM．Theresultsshowthattwo-stagelong-termagingof7050aluminumalloybothofhardnessandstrengthpropertieshavedoublepeaksandthehardnessandstrenghofsecondpeakareslightlyhigherthanthefirstpeak's．TherelationmodelbetweenthehardnesswithagingtimeandagingofthestructurefrommeltinghasbeenestablishedwiththeF-Rsourcemovementcriticalshearstresstheoryandexplainthestrengthenmechanismofsecond-phaseparticlesinthesecondpeakofthe7050aluminumalloy．Ch5fig．1tab．14ref．Keywordsmetallographicanalysis7050aluminumalloytwo-stagedoublepeakage-hardeningproperties07050Al-Zn-Mg-Cu、、1-580674752。7717521SCC1。8701275097208。97000。29420118LightIndustryMachineryVol．29No．4Aug．2011、。7050、F-R。。1ALCOA55mm7050115mm×10mm×10mm470±5℃70min±1℃。A1110℃2150165℃。B1120℃2150165℃。HR-150。GB/T16865-1997AG-10TA。XRDXHitachiS-4700SEM2。17050/%Table1Chemicalcompositionof7050aluminumalloyZnMgCuTiMnCrFeSiAl6．242．252．320．140．300．250．110．07bal．22．1170501110℃8h2150℃165℃1120℃8h2150℃165℃。12M。7050、21。141ac1、1cd2。1120℃2150℃192．3HRBσs=579MPaδ=14．1。“”82．4HRBσs=552MPaδ=14．8292．9HRBσs=586MPaδ=14．5。2．2XRD27050XRD1C4XRDA117hαALMgZn2101MgZn2。BCDMgZn2DB。Bη'MgZn2、Cη'MgZn2ηMgZn2。DηMgZn2。。2．3SEM370501120℃×8h2SEM。3a120℃×8h+150℃×17h3b120℃×8h+150℃×33h3c120℃×8h+150℃×45h3d120℃×8h+150℃×50h。4XRD。3a2αAL3b2cη'MgZn2ηMgZn2αAL。dη11。3TcGPGPGP。GP2。。、3·22·LightIndustryMachinery201141、Figure1Curvesofhardnessandstrengthunderdifferentagingtemperature120℃×8h+150℃/～hA117hB33hC245hD50h27050XRDFigure2X-raydiffractionphaseofdifferentagingtimeof7050aluminumalloy11。GPη'η'η2、21。1。212。1abcdη'GPGP。1GP2η'122。GP。247050。2、。。2222。·32··7050322Figure3Secondmorphologyofthetestalloysamplestreatedbydifferentthesecondagingprocesses47050Figure4Relationofthe7050aluminumalloybetweenthehardnesswithagingtimeandagingofthestructurefrommelting22。1c45h586MPaG=26．1GMPaJade6．0a=0．404900nmF-R1425τb2LτbL2T。τbL=2T=2×12Gb2τ=GbLσs=586MPaτs=12σs=293MPab=a2110=槡22a=1．4142×0．404900=0．2862643nm1102L=26．1×103×0．2862643293=25．50nm70502225．50nm。70502100nm1。13。52Figure5Dislocationstobypasstheresistanceofthesecondphasediagram2“”141η'η'η'GPη'。7050·42·LightIndustryMachinery20114。120℃×8h+150℃×45h2T650nm。2。417050、221、。1GP2η'GPη'GPGP。22222。2。70502225．50nm100nm、。References1．J．20102844-8．2．J．2008263103-106．3RAMGOPALTGOUMAPIGTANKELGS．Roleofgrain-boundaryprecipitatesandsolute-depletedzoneontheintergranularcorrosionofalloy7150J．Corrosion2002588687-697．4．7xxxJ．200728459-63．5．AgAl-Zn-Mg-CuJ．200630320-21．6．7475Al-Zn-Mg-CuJ．1992215-18．7．7175“”J．1996251-54．8．J．2007351236-40．9．7xxx“”J．200938293-97．10GRAZDAAWARMUZEKMWIERZCHOWSKINW．DTAinvestigationoftheretrogressionandreageinginsomeAlZnMgCualloysJ．ThermchimicaActa1997303197-202．11FROWNBF．StresscorrosioncrackinginhighstrengthsteelsandintitaniumandaluminumalloysR．WashingtonNavalResearchLaboratory1972333-34．12．7B04J．2007172248-253．13．M．2000308．14．74757050J．19922檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪15-18．20。。1×1011～1×1014N/m30.55MPa1．5%4．89MPa4．5%。References1．M．1999．2YUANJulongWANGZhiweiHONGTaoetal．Asemi-fixedabrasivemachiningtechniqueJ．JournalofMicromechanicsMicroengneering2009191-7．3ZHAOPCHENJJYANGFetal．Observationinthesurfaceroughnessofsiliconwaferduringsemi-fixedabrasivemachiningwithlargegrainsJ．AdvancedMaterialsResearch200969/70253-257．4YUANJLTAOLWANGZWetal．Surfacelappingbysemi-bondedabrasivegrindingplateforcoppersubstratesofamorphousNi-Pd-PalloyfilmsJ．AdvancedMaterialsResearch200853/54141-146．5LVXYUANJL．Studyonsemi-fixedabrasivelappingofultra-thinsilverelectrodelayerJ．AdvancedMaterialsResearch200969/70225-228．6CUNDALLPASTRUCKODL．AdiscretenumericalmodelforgranularassemblesJ．Geotechnique197929147-65．7ZHOUJianCHIYongCHIYuweietal．ThemethodofparticleflowandPFC2DJ．RockandSoilMechanics2000213271-274．8ItascaConsultingGroupInc．PFC2Dparticleflowcodein2dimensionstheoryandbackgroundR．MinnesotaUSAItascaConsultingGroupInc．2002．9．“”J．2009206714-718．·52··7050